- 26 3月, 2021 2 次提交
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由 Nathan Chancellor 提交于
When cross compiling x86 on an ARM machine with clang, there are several errors along the lines of: arch/x86/include/asm/string_64.h:27:10: error: invalid output constraint '=&c' in asm This happens because the compressed boot Makefile reassigns KBUILD_CFLAGS and drops the clang flags that set the target architecture ('--target=') and the path to the GNU cross tools ('--prefix='), meaning that the host architecture is targeted. These flags are available as $(CLANG_FLAGS) from the main Makefile so add them to the compressed boot folder's KBUILD_CFLAGS so that cross compiling works as expected. Signed-off-by: NNathan Chancellor <nathan@kernel.org> Signed-off-by: NBorislav Petkov <bp@suse.de> Acked-by: NArd Biesheuvel <ardb@kernel.org> Link: https://lkml.kernel.org/r/20210326000435.4785-3-nathan@kernel.org
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由 John Millikin 提交于
When cross-compiling with Clang, the `$(CLANG_FLAGS)' variable contains additional flags needed to build C and assembly sources for the target platform. Normally this variable is automatically included in `$(KBUILD_CFLAGS)' via the top-level Makefile. The x86 real-mode makefile builds `$(REALMODE_CFLAGS)' from a plain assignment and therefore drops the Clang flags. This causes Clang to not recognize x86-specific assembler directives: arch/x86/realmode/rm/header.S:36:1: error: unknown directive .type real_mode_header STT_OBJECT ; .size real_mode_header, .-real_mode_header ^ Explicit propagation of `$(CLANG_FLAGS)' to `$(REALMODE_CFLAGS)', which is inherited by real-mode make rules, fixes cross-compilation with Clang for x86 targets. Relevant flags: * `--target' sets the target architecture when cross-compiling. This flag must be set for both compilation and assembly (`KBUILD_AFLAGS') to support architecture-specific assembler directives. * `-no-integrated-as' tells clang to assemble with GNU Assembler instead of its built-in LLVM assembler. This flag is set by default unless `LLVM_IAS=1' is set, because the LLVM assembler can't yet parse certain GNU extensions. Signed-off-by: NJohn Millikin <john@john-millikin.com> Signed-off-by: NNathan Chancellor <nathan@kernel.org> Signed-off-by: NBorislav Petkov <bp@suse.de> Acked-by: NArd Biesheuvel <ardb@kernel.org> Tested-by: NSedat Dilek <sedat.dilek@gmail.com> Link: https://lkml.kernel.org/r/20210326000435.4785-2-nathan@kernel.org
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- 20 3月, 2021 1 次提交
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由 Johan Hovold 提交于
Architectures that describe the CPU topology in devicetree and do not have an identity mapping between physical and logical CPU ids must override the default implementation of arch_match_cpu_phys_id(). Failing to do so breaks CPU devicetree-node lookups using of_get_cpu_node() and of_cpu_device_node_get() which several drivers rely on. It also causes the CPU struct devices exported through sysfs to point to the wrong devicetree nodes. On x86, CPUs are described in devicetree using their APIC ids and those do not generally coincide with the logical ids, even if CPU0 typically uses APIC id 0. Add the missing implementation of arch_match_cpu_phys_id() so that CPU-node lookups work also with SMP. Apart from fixing the broken sysfs devicetree-node links this likely does not affect current users of mainline kernels on x86. Fixes: 4e07db9c ("x86/devicetree: Use CPU description from Device Tree") Signed-off-by: NJohan Hovold <johan@kernel.org> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210312092033.26317-1-johan@kernel.org
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- 19 3月, 2021 4 次提交
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由 Thomas Gleixner 提交于
Vitaly ran into an issue with hotplugging CPU0 on an Amazon instance where the matrix allocator claimed to be out of vectors. He analyzed it down to the point that IRQ2, the PIC cascade interrupt, which is supposed to be not ever routed to the IO/APIC ended up having an interrupt vector assigned which got moved during unplug of CPU0. The underlying issue is that IRQ2 for various reasons (see commit af174783 ("x86: I/O APIC: Never configure IRQ2" for details) is treated as a reserved system vector by the vector core code and is not accounted as a regular vector. The Amazon BIOS has an routing entry of pin2 to IRQ2 which causes the IO/APIC setup to claim that interrupt which is granted by the vector domain because there is no sanity check. As a consequence the allocation counter of CPU0 underflows which causes a subsequent unplug to fail with: [ ... ] CPU 0 has 4294967295 vectors, 589 available. Cannot disable CPU There is another sanity check missing in the matrix allocator, but the underlying root cause is that the IO/APIC code lost the IRQ2 ignore logic during the conversion to irqdomains. For almost 6 years nobody complained about this wreckage, which might indicate that this requirement could be lifted, but for any system which actually has a PIC IRQ2 is unusable by design so any routing entry has no effect and the interrupt cannot be connected to a device anyway. Due to that and due to history biased paranoia reasons restore the IRQ2 ignore logic and treat it as non existent despite a routing entry claiming otherwise. Fixes: d32932d0 ("x86/irq: Convert IOAPIC to use hierarchical irqdomain interfaces") Reported-by: NVitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Tested-by: NVitaly Kuznetsov <vkuznets@redhat.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210318192819.636943062@linutronix.de
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由 Wanpeng Li 提交于
After commit 997acaf6 (lockdep: report broken irq restoration), the guest splatting below during boot: raw_local_irq_restore() called with IRQs enabled WARNING: CPU: 1 PID: 169 at kernel/locking/irqflag-debug.c:10 warn_bogus_irq_restore+0x26/0x30 Modules linked in: hid_generic usbhid hid CPU: 1 PID: 169 Comm: systemd-udevd Not tainted 5.11.0+ #25 RIP: 0010:warn_bogus_irq_restore+0x26/0x30 Call Trace: kvm_wait+0x76/0x90 __pv_queued_spin_lock_slowpath+0x285/0x2e0 do_raw_spin_lock+0xc9/0xd0 _raw_spin_lock+0x59/0x70 lockref_get_not_dead+0xf/0x50 __legitimize_path+0x31/0x60 legitimize_root+0x37/0x50 try_to_unlazy_next+0x7f/0x1d0 lookup_fast+0xb0/0x170 path_openat+0x165/0x9b0 do_filp_open+0x99/0x110 do_sys_openat2+0x1f1/0x2e0 do_sys_open+0x5c/0x80 __x64_sys_open+0x21/0x30 do_syscall_64+0x32/0x50 entry_SYSCALL_64_after_hwframe+0x44/0xae The new consistency checking, expects local_irq_save() and local_irq_restore() to be paired and sanely nested, and therefore expects local_irq_restore() to be called with irqs disabled. The irqflags handling in kvm_wait() which ends up doing: local_irq_save(flags); safe_halt(); local_irq_restore(flags); instead triggers it. This patch fixes it by using local_irq_disable()/enable() directly. Cc: Thomas Gleixner <tglx@linutronix.de> Reported-by: NDmitry Vyukov <dvyukov@google.com> Signed-off-by: NWanpeng Li <wanpengli@tencent.com> Message-Id: <1615791328-2735-1-git-send-email-wanpengli@tencent.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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由 Wanpeng Li 提交于
In order to deal with noncoherent DMA, we should execute wbinvd on all dirty pCPUs when guest wbinvd exits to maintain data consistency. smp_call_function_many() does not execute the provided function on the local core, therefore replace it by on_each_cpu_mask(). Reported-by: NNadav Amit <namit@vmware.com> Cc: Nadav Amit <namit@vmware.com> Signed-off-by: NWanpeng Li <wanpengli@tencent.com> Message-Id: <1615517151-7465-1-git-send-email-wanpengli@tencent.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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由 Sean Christopherson 提交于
Fix a plethora of issues with MSR filtering by installing the resulting filter as an atomic bundle instead of updating the live filter one range at a time. The KVM_X86_SET_MSR_FILTER ioctl() isn't truly atomic, as the hardware MSR bitmaps won't be updated until the next VM-Enter, but the relevant software struct is atomically updated, which is what KVM really needs. Similar to the approach used for modifying memslots, make arch.msr_filter a SRCU-protected pointer, do all the work configuring the new filter outside of kvm->lock, and then acquire kvm->lock only when the new filter has been vetted and created. That way vCPU readers either see the old filter or the new filter in their entirety, not some half-baked state. Yuan Yao pointed out a use-after-free in ksm_msr_allowed() due to a TOCTOU bug, but that's just the tip of the iceberg... - Nothing is __rcu annotated, making it nigh impossible to audit the code for correctness. - kvm_add_msr_filter() has an unpaired smp_wmb(). Violation of kernel coding style aside, the lack of a smb_rmb() anywhere casts all code into doubt. - kvm_clear_msr_filter() has a double free TOCTOU bug, as it grabs count before taking the lock. - kvm_clear_msr_filter() also has memory leak due to the same TOCTOU bug. The entire approach of updating the live filter is also flawed. While installing a new filter is inherently racy if vCPUs are running, fixing the above issues also makes it trivial to ensure certain behavior is deterministic, e.g. KVM can provide deterministic behavior for MSRs with identical settings in the old and new filters. An atomic update of the filter also prevents KVM from getting into a half-baked state, e.g. if installing a filter fails, the existing approach would leave the filter in a half-baked state, having already committed whatever bits of the filter were already processed. [*] https://lkml.kernel.org/r/20210312083157.25403-1-yaoyuan0329os@gmail.com Fixes: 1a155254 ("KVM: x86: Introduce MSR filtering") Cc: stable@vger.kernel.org Cc: Alexander Graf <graf@amazon.com> Reported-by: NYuan Yao <yaoyuan0329os@gmail.com> Signed-off-by: NSean Christopherson <seanjc@google.com> Message-Id: <20210316184436.2544875-2-seanjc@google.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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- 18 3月, 2021 3 次提交
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由 Vitaly Kuznetsov 提交于
When guest opts for re-enlightenment notifications upon migration, it is in its right to assume that TSC page values never change (as they're only supposed to change upon migration and the host has to keep things as they are before it receives confirmation from the guest). This is mostly true until the guest is migrated somewhere. KVM userspace (e.g. QEMU) will trigger masterclock update by writing to HV_X64_MSR_REFERENCE_TSC, by calling KVM_SET_CLOCK,... and as TSC value and kvmclock reading drift apart (even slightly), the update causes TSC page values to change. The issue at hand is that when Hyper-V is migrated, it uses stale (cached) TSC page values to compute the difference between its own clocksource (provided by KVM) and its guests' TSC pages to program synthetic timers and in some cases, when TSC page is updated, this puts all stimer expirations in the past. This, in its turn, causes an interrupt storm and L2 guests not making much forward progress. Note, KVM doesn't fully implement re-enlightenment notification. Basically, the support for reenlightenment MSRs is just a stub and userspace is only expected to expose the feature when TSC scaling on the expected destination hosts is available. With TSC scaling, no real re-enlightenment is needed as TSC frequency doesn't change. With TSC scaling becoming ubiquitous, it likely makes little sense to fully implement re-enlightenment in KVM. Prevent TSC page from being updated after migration. In case it's not the guest who's initiating the change and when TSC page is already enabled, just keep it as it is: TSC value is supposed to be preserved across migration and TSC frequency can't change with re-enlightenment enabled. The guest is doomed anyway if any of this is not true. Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210316143736.964151-5-vkuznets@redhat.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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由 Vitaly Kuznetsov 提交于
Create an infrastructure for tracking Hyper-V TSC page status, i.e. if it was updated from guest/host side or if we've failed to set it up (because e.g. guest wrote some garbage to HV_X64_MSR_REFERENCE_TSC) and there's no need to retry. Also, in a hypothetical situation when we are in 'always catchup' mode for TSC we can now avoid contending 'hv->hv_lock' on every guest enter by setting the state to HV_TSC_PAGE_BROKEN after compute_tsc_page_parameters() returns false. Check for HV_TSC_PAGE_SET state instead of '!hv->tsc_ref.tsc_sequence' in get_time_ref_counter() to properly handle the situation when we failed to write the updated TSC page values to the guest. Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210316143736.964151-4-vkuznets@redhat.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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由 Leon Romanovsky 提交于
MODULE_SUPPORTED_DEVICE was added in pre-git era and never was implemented. We can safely remove it, because the kernel has grown to have many more reliable mechanisms to determine if device is supported or not. Signed-off-by: NLeon Romanovsky <leonro@nvidia.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 17 3月, 2021 19 次提交
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由 Vitaly Kuznetsov 提交于
When KVM_REQ_MASTERCLOCK_UPDATE request is issued (e.g. after migration) we need to make sure no vCPU sees stale values in PV clock structures and thus all vCPUs are kicked with KVM_REQ_CLOCK_UPDATE. Hyper-V TSC page clocksource is global and kvm_guest_time_update() only updates in on vCPU0 but this is not entirely correct: nothing blocks some other vCPU from entering the guest before we finish the update on CPU0 and it can read stale values from the page. Invalidate TSC page in kvm_gen_update_masterclock() to switch all vCPUs to using MSR based clocksource (HV_X64_MSR_TIME_REF_COUNT). Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210316143736.964151-3-vkuznets@redhat.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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由 Vitaly Kuznetsov 提交于
HV_X64_MSR_TSC_EMULATION_STATUS indicates whether TSC accesses are emulated after migration (to accommodate for a different host TSC frequency when TSC scaling is not supported; we don't implement this in KVM). Guest can use the same MSR to stop TSC access emulation by writing zero. Writing anything else is forbidden. Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210316143736.964151-2-vkuznets@redhat.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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由 Kefeng Wang 提交于
There are two issues for RV32, 1) if use FLATMEM, it is useless to enable SPARSEMEM_STATIC. 2) if use SPARSMEM, both SPARSEMEM_VMEMMAP and SPARSEMEM_STATIC is enabled. Fixes: d95f1a54 ("RISC-V: Implement sparsemem") Signed-off-by: NKefeng Wang <wangkefeng.wang@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: NPalmer Dabbelt <palmerdabbelt@google.com>
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由 Palmer Dabbelt 提交于
Without this I get a missing prototype warning. Reported-by: Nkernel test robot <lkp@intel.com> Fixes: e178d670 ("riscv/kasan: add KASAN_VMALLOC support") Cc: stable@vger.kernel.org Signed-off-by: NPalmer Dabbelt <palmerdabbelt@google.com>
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由 Alexandre Ghiti 提交于
Make sure that writes to kernel page table during KASAN vmalloc initialization are made visible by adding a sfence.vma. Signed-off-by: NAlexandre Ghiti <alex@ghiti.fr> Reviewed-by: NPalmer Dabbelt <palmerdabbelt@google.com> Fixes: e178d670 ("riscv/kasan: add KASAN_VMALLOC support") Cc: stable@vger.kernel.org Signed-off-by: NPalmer Dabbelt <palmerdabbelt@google.com>
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由 Geert Uytterhoeven 提交于
init_resources() allocates an array of resources, based on the current total number of memory regions and reserved memory regions. However, allocating this array using memblock_alloc() might increase the number of reserved memory regions. If that happens, populating the array later based on the new number of regions will cause out-of-bounds writes beyond the end of the allocated array. Fix this by allocating one more entry, which may or may not be used. Fixes: 797f0375 ("RISC-V: Do not allocate memblock while iterating reserved memblocks") Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: NAtish Patra <atish.patra@wdc.com> Cc: stable@vger.kernel.org Signed-off-by: NPalmer Dabbelt <palmerdabbelt@google.com>
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由 Damien Le Moal 提交于
When CONFIG_SOC_CANAAN is selected, the K210 sysctl driver is always compiled. Since this driver early init function calls the function k210_clk_early_init() implemented by the K210 clk driver, this driver must also always be selected for compilation ot avoid build failures. Avoid such build failures by always selecting CONFIG_COMMON_CLK and CONFIG_COMMON_CLK_K210 when CONFIG_SOC_CANAAN is enabled. Reported-by: Nkernel test robot <lkp@intel.com> Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com> Fixes: c6ca7616 ("clk: Add RISC-V Canaan Kendryte K210 clock driver") Cc: stable@vger.kernel.org Signed-off-by: NPalmer Dabbelt <palmerdabbelt@google.com>
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由 Colin Ian King 提交于
There is a spelling mistake in a comment, fix it. Signed-off-by: NColin Ian King <colin.king@canonical.com> Signed-off-by: NPalmer Dabbelt <palmerdabbelt@google.com>
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由 kernel test robot 提交于
Use BUG_ON instead of a if condition followed by BUG. Generated by: scripts/coccinelle/misc/bugon.cocci Fixes: c22b0bcb ("riscv: Add kprobes supported") CC: Guo Ren <guoren@linux.alibaba.com> Reported-by: Nkernel test robot <lkp@intel.com> Signed-off-by: Nkernel test robot <lkp@intel.com> Signed-off-by: NJulia Lawall <julia.lawall@inria.fr> Reviewed-by: NPekka Enberg <penberg@kernel.org> Signed-off-by: NPalmer Dabbelt <palmerdabbelt@google.com>
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由 Paul Cercueil 提交于
Commit 6654111c ("MIPS: vmlinux.lds.S: align raw appended dtb to 8 bytes") changed the alignment from STRUCT_ALIGNMENT bytes to 8 bytes. The commit's message makes it sound like it was actually done on purpose, but this is not the case. The commit was written when raw appended dtb were not aligned at all. The STRUCT_ALIGN() was added a few days before, in commit 7a05293a ("MIPS: boot/compressed: Copy DTB to aligned address"). The true purpose of the commit was not to align specifically to 8 bytes, but to make sure that the generated vmlinux' size was properly padded to the alignment required for DTBs. While the switch to 8-byte alignment worked for vmlinux-appended dtb blobs, it broke vmlinuz-appended dtb blobs, as the decompress routine moves the blob to a STRUCT_ALIGNMENT aligned address. Fix this by changing the raw appended dtb blob alignment from 8 bytes back to STRUCT_ALIGNMENT bytes in vmlinux.lds.S. Fixes: 6654111c ("MIPS: vmlinux.lds.S: align raw appended dtb to 8 bytes") Cc: Bjørn Mork <bjorn@mork.no> Signed-off-by: NPaul Cercueil <paul@crapouillou.net> Signed-off-by: NThomas Bogendoerfer <tsbogend@alpha.franken.de>
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由 Oleg Nesterov 提交于
Save the current_thread_info()->status of X86 in the new restart_block->arch_data field so TS_COMPAT_RESTART can be removed again. Signed-off-by: NOleg Nesterov <oleg@redhat.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210201174716.GA17898@redhat.com
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由 Oleg Nesterov 提交于
The comment in get_nr_restart_syscall() says: * The problem is that we can get here when ptrace pokes * syscall-like values into regs even if we're not in a syscall * at all. Yes, but if not in a syscall then the status & (TS_COMPAT|TS_I386_REGS_POKED) check below can't really help: - TS_COMPAT can't be set - TS_I386_REGS_POKED is only set if regs->orig_ax was changed by 32bit debugger; and even in this case get_nr_restart_syscall() is only correct if the tracee is 32bit too. Suppose that a 64bit debugger plays with a 32bit tracee and * Tracee calls sleep(2) // TS_COMPAT is set * User interrupts the tracee by CTRL-C after 1 sec and does "(gdb) call func()" * gdb saves the regs by PTRACE_GETREGS * does PTRACE_SETREGS to set %rip='func' and %orig_rax=-1 * PTRACE_CONT // TS_COMPAT is cleared * func() hits int3. * Debugger catches SIGTRAP. * Restore original regs by PTRACE_SETREGS. * PTRACE_CONT get_nr_restart_syscall() wrongly returns __NR_restart_syscall==219, the tracee calls ia32_sys_call_table[219] == sys_madvise. Add the sticky TS_COMPAT_RESTART flag which survives after return to user mode. It's going to be removed in the next step again by storing the information in the restart block. As a further cleanup it might be possible to remove also TS_I386_REGS_POKED with that. Test-case: $ cvs -d :pserver:anoncvs:anoncvs@sourceware.org:/cvs/systemtap co ptrace-tests $ gcc -o erestartsys-trap-debuggee ptrace-tests/tests/erestartsys-trap-debuggee.c --m32 $ gcc -o erestartsys-trap-debugger ptrace-tests/tests/erestartsys-trap-debugger.c -lutil $ ./erestartsys-trap-debugger Unexpected: retval 1, errno 22 erestartsys-trap-debugger: ptrace-tests/tests/erestartsys-trap-debugger.c:421 Fixes: 609c19a3 ("x86/ptrace: Stop setting TS_COMPAT in ptrace code") Reported-by: NJan Kratochvil <jan.kratochvil@redhat.com> Signed-off-by: NOleg Nesterov <oleg@redhat.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210201174709.GA17895@redhat.com
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由 Oleg Nesterov 提交于
Move TS_COMPAT back to asm/thread_info.h, close to TS_I386_REGS_POKED. It was moved to asm/processor.h by b9d989c7 ("x86/asm: Move the thread_info::status field to thread_struct"), then later 37a8f7c3 ("x86/asm: Move 'status' from thread_struct to thread_info") moved the 'status' field back but TS_COMPAT was forgotten. Preparatory patch to fix the COMPAT case for get_nr_restart_syscall() Fixes: 609c19a3 ("x86/ptrace: Stop setting TS_COMPAT in ptrace code") Signed-off-by: NOleg Nesterov <oleg@redhat.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210201174649.GA17880@redhat.com
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由 Kan Liang 提交于
On a Haswell machine, the perf_fuzzer managed to trigger this message: [117248.075892] unchecked MSR access error: WRMSR to 0x3f1 (tried to write 0x0400000000000000) at rIP: 0xffffffff8106e4f4 (native_write_msr+0x4/0x20) [117248.089957] Call Trace: [117248.092685] intel_pmu_pebs_enable_all+0x31/0x40 [117248.097737] intel_pmu_enable_all+0xa/0x10 [117248.102210] __perf_event_task_sched_in+0x2df/0x2f0 [117248.107511] finish_task_switch.isra.0+0x15f/0x280 [117248.112765] schedule_tail+0xc/0x40 [117248.116562] ret_from_fork+0x8/0x30 A fake event called VLBR_EVENT may use the bit 58 of the PEBS_ENABLE, if the precise_ip is set. The bit 58 is reserved by the HW. Accessing the bit causes the unchecked MSR access error. The fake event doesn't support PEBS. The case should be rejected. Fixes: 097e4311 ("perf/x86: Add constraint to create guest LBR event without hw counter") Reported-by: NVince Weaver <vincent.weaver@maine.edu> Signed-off-by: NKan Liang <kan.liang@linux.intel.com> Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1615555298-140216-2-git-send-email-kan.liang@linux.intel.com
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由 Kan Liang 提交于
A repeatable crash can be triggered by the perf_fuzzer on some Haswell system. https://lore.kernel.org/lkml/7170d3b-c17f-1ded-52aa-cc6d9ae999f4@maine.edu/ For some old CPUs (HSW and earlier), the PEBS status in a PEBS record may be mistakenly set to 0. To minimize the impact of the defect, the commit was introduced to try to avoid dropping the PEBS record for some cases. It adds a check in the intel_pmu_drain_pebs_nhm(), and updates the local pebs_status accordingly. However, it doesn't correct the PEBS status in the PEBS record, which may trigger the crash, especially for the large PEBS. It's possible that all the PEBS records in a large PEBS have the PEBS status 0. If so, the first get_next_pebs_record_by_bit() in the __intel_pmu_pebs_event() returns NULL. The at = NULL. Since it's a large PEBS, the 'count' parameter must > 1. The second get_next_pebs_record_by_bit() will crash. Besides the local pebs_status, correct the PEBS status in the PEBS record as well. Fixes: 01330d72 ("perf/x86: Allow zero PEBS status with only single active event") Reported-by: NVince Weaver <vincent.weaver@maine.edu> Suggested-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: NKan Liang <kan.liang@linux.intel.com> Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1615555298-140216-1-git-send-email-kan.liang@linux.intel.com
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由 Sean Christopherson 提交于
Store the address space ID in the TDP iterator so that it can be retrieved without having to bounce through the root shadow page. This streamlines the code and fixes a Sparse warning about not properly using rcu_dereference() when grabbing the ID from the root on the fly. Reported-by: Nkernel test robot <lkp@intel.com> Signed-off-by: NSean Christopherson <seanjc@google.com> Signed-off-by: NBen Gardon <bgardon@google.com> Message-Id: <20210315233803.2706477-5-bgardon@google.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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由 Ben Gardon 提交于
In tdp_mmu_iter_cond_resched there is a call to tdp_iter_start which causes the iterator to continue its walk over the paging structure from the root. This is needed after a yield as paging structure could have been freed in the interim. The tdp_iter_start call is not very clear and something of a hack. It requires exposing tdp_iter fields not used elsewhere in tdp_mmu.c and the effect is not obvious from the function name. Factor a more aptly named function out of tdp_iter_start and call it from tdp_mmu_iter_cond_resched and tdp_iter_start. No functional change intended. Signed-off-by: NBen Gardon <bgardon@google.com> Message-Id: <20210315233803.2706477-4-bgardon@google.com> Reviewed-by: NSean Christopherson <seanjc@google.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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由 Ben Gardon 提交于
Fix a missing rcu_dereference in tdp_mmu_zap_spte_atomic. Reported-by: Nkernel test robot <lkp@intel.com> Signed-off-by: NBen Gardon <bgardon@google.com> Message-Id: <20210315233803.2706477-3-bgardon@google.com> Reviewed-by: NSean Christopherson <seanjc@google.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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由 Ben Gardon 提交于
The pt passed into handle_removed_tdp_mmu_page does not need RCU protection, as it is not at any risk of being freed by another thread at that point. However, the implicit cast from tdp_sptep_t to u64 * dropped the __rcu annotation without a proper rcu_derefrence. Fix this by passing the pt as a tdp_ptep_t and then rcu_dereferencing it in the function. Suggested-by: NSean Christopherson <seanjc@google.com> Reported-by: Nkernel test robot <lkp@intel.com> Signed-off-by: NBen Gardon <bgardon@google.com> Message-Id: <20210315233803.2706477-2-bgardon@google.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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- 16 3月, 2021 3 次提交
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由 Niklas Schnelle 提交于
In commit 05bc1be6 ("s390/pci: create zPCI bus") we removed the pci_dev_put() call matching the earlier pci_get_slot() done as part of __zpci_event_availability(). This was based on the wrong understanding that the device_put() done as part of pci_destroy_device() would counter the pci_get_slot() when it only counters the initial reference. This same understanding and existing bad example also lead to not doing a pci_dev_put() in zpci_remove_device(). Since releasing the PCI devices, unlike releasing the PCI slot, does not print any debug message for testing I added one in pci_release_dev(). This revealed that we are indeed leaking the PCI device on PCI hotunplug. Further testing also revealed another missing pci_dev_put() in disable_slot(). Fix this by adding the missing pci_dev_put() in disable_slot() and fix zpci_remove_device() with the correct pci_dev_put() calls. Also instead of calling pci_get_slot() in __zpci_event_availability() to determine if a PCI device is registered and then doing the same again in zpci_remove_device() do this once in zpci_remove_device() which makes sure that the pdev in __zpci_event_availability() is only used for the result of pci_scan_single_device() which does not need a reference count decremnt as its ownership goes to the PCI bus. Also move the check if zdev->zbus->bus is set into zpci_remove_device() since it may be that we're removing a device with devfn != 0 which never had a PCI bus. So we can still set the pdev->error_state to indicate that the device is not usable anymore, add a flag to set the error state. Fixes: 05bc1be6 ("s390/pci: create zPCI bus") Cc: <stable@vger.kernel.org> # 5.8+: e1bff843 s390/pci: remove superfluous zdev->zbus check Cc: <stable@vger.kernel.org> # 5.8+: ba764dd7 s390/pci: refactor zpci_create_device() Cc: <stable@vger.kernel.org> # 5.8+ Reviewed-by: NMatthew Rosato <mjrosato@linux.ibm.com> Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>
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由 Gerald Schaefer 提交于
Commit 152e9b86 ("s390/vtime: steal time exponential moving average") inadvertently changed the input value for account_steal_time() from "cputime_to_nsecs(steal)" to just "steal", resulting in broken increased steal time accounting. Fix this by changing it back to "cputime_to_nsecs(steal)". Fixes: 152e9b86 ("s390/vtime: steal time exponential moving average") Cc: <stable@vger.kernel.org> # 5.1 Reported-by: NSabine Forkel <sabine.forkel@de.ibm.com> Reviewed-by: NHeiko Carstens <hca@linux.ibm.com> Signed-off-by: NGerald Schaefer <gerald.schaefer@linux.ibm.com> Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>
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由 Thomas Richter 提交于
The following BUG message was triggered repeatedly when complete counter sets are extracted from the CPUMF: BUG: using smp_processor_id() in preemptible [00000000] code: psvc-readsets/7759 caller is cf_diag_needspace+0x2c/0x100 CPU: 7 PID: 7759 Comm: psvc-readsets Not tainted 5.12.0 Hardware name: IBM 3906 M03 703 (LPAR) Call Trace: [<00000000c7043f78>] show_stack+0x90/0xf8 [<00000000c705776a>] dump_stack+0xba/0x108 [<00000000c705d91c>] check_preemption_disabled+0xec/0xf0 [<00000000c63eb1c4>] cf_diag_needspace+0x2c/0x100 [<00000000c63ecbcc>] cf_diag_ioctl_start+0x10c/0x240 [<00000000c63ece9a>] cf_diag_ioctl+0x19a/0x238 [<00000000c675f3f4>] __s390x_sys_ioctl+0xc4/0x100 [<00000000c63ca762>] do_syscall+0x82/0xd0 [<00000000c705bdd8>] __do_syscall+0xc0/0xd8 [<00000000c706d532>] system_call+0x72/0x98 2 locks held by psvc-readsets/7759: #0: 00000000c75a57c0 (cpu_hotplug_lock){++++}-{0:0}, at: cf_diag_ioctl+0x44/0x238 #1: 00000000c75a3078 (cf_diag_ctrset_mutex){+.+.}-{3:3}, at: cf_diag_ioctl+0x54/0x238 This issue is a missing get_cpu_ptr/put_cpu_ptr pair in function cf_diag_needspace. Add it. Fixes: cf6acb8b ("s390/cpumf: Add support for complete counter set extraction") Reviewed-by: NHeiko Carstens <hca@linux.ibm.com> Signed-off-by: NThomas Richter <tmricht@linux.ibm.com> Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>
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- 14 3月, 2021 4 次提交
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由 Christophe Leroy 提交于
The code relies on constant folding of cpu_has_feature() based on possible and always true values as defined per CPU_FTRS_ALWAYS and CPU_FTRS_POSSIBLE. Build failure is encountered with for instance book3e_all_defconfig on kisskb in the AMDGPU driver which uses cpu_has_feature(CPU_FTR_VSX_COMP) to decide whether calling kernel_enable_vsx() or not. The failure is due to cpu_has_feature() not being inlined with that configuration with gcc 4.9. In the same way as commit acdad8fb ("powerpc: Force inlining of mmu_has_feature to fix build failure"), for inlining of cpu_has_feature(). Signed-off-by: NChristophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/b231dfa040ce4cc37f702f5c3a595fdeabfe0462.1615378209.git.christophe.leroy@csgroup.eu
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由 Christophe Leroy 提交于
With some defconfig including CONFIG_CC_OPTIMIZE_FOR_SIZE, (for instance mvme5100_defconfig and ps3_defconfig), gcc 5 generates a call to _restgpr_31_x. Until recently it went unnoticed, but commit 42ed6d56 ("powerpc/vdso: Block R_PPC_REL24 relocations") made it rise to the surface. Provide that function (copied from lib/crtsavres.S) in gettimeofday.S Fixes: ab037dd8 ("powerpc/vdso: Switch VDSO to generic C implementation.") Signed-off-by: NChristophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/a7aa198a88bcd33c6e35e99f70f86c7b7f2f9440.1615270757.git.christophe.leroy@csgroup.eu
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由 Sergei Trofimovich 提交于
In https://bugs.gentoo.org/769614 Dmitry noticed that `ptrace(PTRACE_GET_SYSCALL_INFO)` does not return error sign properly. The bug is in mismatch between get/set errors: static inline long syscall_get_error(struct task_struct *task, struct pt_regs *regs) { return regs->r10 == -1 ? regs->r8:0; } static inline long syscall_get_return_value(struct task_struct *task, struct pt_regs *regs) { return regs->r8; } static inline void syscall_set_return_value(struct task_struct *task, struct pt_regs *regs, int error, long val) { if (error) { /* error < 0, but ia64 uses > 0 return value */ regs->r8 = -error; regs->r10 = -1; } else { regs->r8 = val; regs->r10 = 0; } } Tested on v5.10 on rx3600 machine (ia64 9040 CPU). Link: https://lkml.kernel.org/r/20210221002554.333076-2-slyfox@gentoo.org Link: https://bugs.gentoo.org/769614Signed-off-by: NSergei Trofimovich <slyfox@gentoo.org> Reported-by: NDmitry V. Levin <ldv@altlinux.org> Reviewed-by: NDmitry V. Levin <ldv@altlinux.org> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Sergei Trofimovich 提交于
In https://bugs.gentoo.org/769614 Dmitry noticed that `ptrace(PTRACE_GET_SYSCALL_INFO)` does not work for syscalls called via glibc's syscall() wrapper. ia64 has two ways to call syscalls from userspace: via `break` and via `eps` instructions. The difference is in stack layout: 1. `eps` creates simple stack frame: no locals, in{0..7} == out{0..8} 2. `break` uses userspace stack frame: may be locals (glibc provides one), in{0..7} == out{0..8}. Both work fine in syscall handling cde itself. But `ptrace(PTRACE_GET_SYSCALL_INFO)` uses unwind mechanism to re-extract syscall arguments but it does not account for locals. The change always skips locals registers. It should not change `eps` path as kernel's handler already enforces locals=0 and fixes `break`. Tested on v5.10 on rx3600 machine (ia64 9040 CPU). Link: https://lkml.kernel.org/r/20210221002554.333076-1-slyfox@gentoo.org Link: https://bugs.gentoo.org/769614Signed-off-by: NSergei Trofimovich <slyfox@gentoo.org> Reported-by: NDmitry V. Levin <ldv@altlinux.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 13 3月, 2021 4 次提交
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由 Wanpeng Li 提交于
Advancing the timer expiration should only be necessary on guest initiated writes. When we cancel the timer and clear .pending during state restore, clear expired_tscdeadline as well. Reviewed-by: NSean Christopherson <seanjc@google.com> Signed-off-by: NWanpeng Li <wanpengli@tencent.com> Message-Id: <1614818118-965-1-git-send-email-wanpengli@tencent.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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由 Sean Christopherson 提交于
If mmu_lock is held for write, don't bother setting !PRESENT SPTEs to REMOVED_SPTE when recursively zapping SPTEs as part of shadow page removal. The concurrent write protections provided by REMOVED_SPTE are not needed, there are no backing page side effects to record, and MMIO SPTEs can be left as is since they are protected by the memslot generation, not by ensuring that the MMIO SPTE is unreachable (which is racy with respect to lockless walks regardless of zapping behavior). Skipping !PRESENT drastically reduces the number of updates needed to tear down sparsely populated MMUs, e.g. when tearing down a 6gb VM that didn't touch much memory, 6929/7168 (~96.6%) of SPTEs were '0' and could be skipped. Avoiding the write itself is likely close to a wash, but avoiding __handle_changed_spte() is a clear-cut win as that involves saving and restoring all non-volatile GPRs (it's a subtly big function), as well as several conditional branches before bailing out. Cc: Ben Gardon <bgardon@google.com> Signed-off-by: NSean Christopherson <seanjc@google.com> Message-Id: <20210310003029.1250571-1-seanjc@google.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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由 Wanpeng Li 提交于
# lscpu Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian CPU(s): 88 On-line CPU(s) list: 0-63 Off-line CPU(s) list: 64-87 # cat /proc/cmdline BOOT_IMAGE=/vmlinuz-5.10.0-rc3-tlinux2-0050+ root=/dev/mapper/cl-root ro rd.lvm.lv=cl/root rhgb quiet console=ttyS0 LANG=en_US .UTF-8 no-kvmclock-vsyscall # echo 1 > /sys/devices/system/cpu/cpu76/online -bash: echo: write error: Cannot allocate memory The per-cpu vsyscall pvclock data pointer assigns either an element of the static array hv_clock_boot (#vCPU <= 64) or dynamically allocated memory hvclock_mem (vCPU > 64), the dynamically memory will not be allocated if kvmclock vsyscall is disabled, this can result in cpu hotpluged fails in kvmclock_setup_percpu() which returns -ENOMEM. It's broken for no-vsyscall and sometimes you end up with vsyscall disabled if the host does something strange. This patch fixes it by allocating this dynamically memory unconditionally even if vsyscall is disabled. Fixes: 6a1cac56 ("x86/kvm: Use __bss_decrypted attribute in shared variables") Reported-by: NZelin Deng <zelin.deng@linux.alibaba.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: stable@vger.kernel.org#v4.19-rc5+ Signed-off-by: NWanpeng Li <wanpengli@tencent.com> Message-Id: <1614130683-24137-1-git-send-email-wanpengli@tencent.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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由 Muhammad Usama Anjum 提交于
This patch adds the annotation to fix the following sparse errors: arch/x86/kvm//x86.c:8147:15: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//x86.c:8147:15: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//x86.c:8147:15: struct kvm_apic_map * arch/x86/kvm//x86.c:10628:16: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//x86.c:10628:16: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//x86.c:10628:16: struct kvm_apic_map * arch/x86/kvm//x86.c:10629:15: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//x86.c:10629:15: struct kvm_pmu_event_filter [noderef] __rcu * arch/x86/kvm//x86.c:10629:15: struct kvm_pmu_event_filter * arch/x86/kvm//lapic.c:267:15: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//lapic.c:267:15: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//lapic.c:267:15: struct kvm_apic_map * arch/x86/kvm//lapic.c:269:9: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//lapic.c:269:9: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//lapic.c:269:9: struct kvm_apic_map * arch/x86/kvm//lapic.c:637:15: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//lapic.c:637:15: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//lapic.c:637:15: struct kvm_apic_map * arch/x86/kvm//lapic.c:994:15: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//lapic.c:994:15: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//lapic.c:994:15: struct kvm_apic_map * arch/x86/kvm//lapic.c:1036:15: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//lapic.c:1036:15: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//lapic.c:1036:15: struct kvm_apic_map * arch/x86/kvm//lapic.c:1173:15: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//lapic.c:1173:15: struct kvm_apic_map [noderef] __rcu * arch/x86/kvm//lapic.c:1173:15: struct kvm_apic_map * arch/x86/kvm//pmu.c:190:18: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//pmu.c:190:18: struct kvm_pmu_event_filter [noderef] __rcu * arch/x86/kvm//pmu.c:190:18: struct kvm_pmu_event_filter * arch/x86/kvm//pmu.c:251:18: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//pmu.c:251:18: struct kvm_pmu_event_filter [noderef] __rcu * arch/x86/kvm//pmu.c:251:18: struct kvm_pmu_event_filter * arch/x86/kvm//pmu.c:522:18: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//pmu.c:522:18: struct kvm_pmu_event_filter [noderef] __rcu * arch/x86/kvm//pmu.c:522:18: struct kvm_pmu_event_filter * arch/x86/kvm//pmu.c:522:18: error: incompatible types in comparison expression (different address spaces): arch/x86/kvm//pmu.c:522:18: struct kvm_pmu_event_filter [noderef] __rcu * arch/x86/kvm//pmu.c:522:18: struct kvm_pmu_event_filter * Signed-off-by: NMuhammad Usama Anjum <musamaanjum@gmail.com> Message-Id: <20210305191123.GA497469@LEGION> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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